Samsung has issued a worldwide recall of its flagship Galaxy Note 7 phablet following the discovery of a “battery cell issue” that reportedly led to explosions — an embarrassing setback for the massive consumer electronics manufacturer.

At a press conference in South Korea, the company explained that the recall would take about two weeks, but declined to explain how much it would cost, CNN reported.

“It is a big amount that is heartbreaking,” said Koh Dong-jin, president of Samsung’s mobile communications business.

“Samsung is committed to producing the highest quality products and we take every incident report from our valued customers very seriously,” the company wrote on its website. “In response to recently reported cases of the new Galaxy Note 7, we conducted a thorough investigation and found a battery cell issue.”

The issue has only been detected in 35 phones, the company claims, without elaborating on what it discovered. But some early users of the device have posted pictures on social media of charred units, CNN said. Samsung says. The company claims to be “currently conducting a thorough inspection with our suppliers to identify possible affected batteries in the market.” It has also stopped sales of the Galaxy Note 7 indefinitely.

The issue is a rare misstep for the company, and a challenge for a phone widely regarded as one of the best on the market. The Samsung Galaxy Note 7 is more popular than even Samsung anticipated, demand that put great pressure on the supply chain. As the company was investigating the issue earlier in the week, it used the demand as an excuse to explain delays in some markets.

“As pre-order results for the Galaxy Note 7 have far exceeded our estimates, its release date in some markets has been adjusted,” said the company in a statement to Reuters. Samsung didn’t give any information about which markets the phone will be delayed in at the time, but some previous reports had indicated that the release was being pushed back in markets like Malaysia, Russia, and Ukraine.

The company said at the time that it was working hard to ensure that it could keep up with demand in the future, and was boosting production in facilities making the Note series of phones. Samsung had a similar issue last year when the Galaxy S6 Edge was released.

Samsung hopes that strong sales of the Note 7 will buoy the company. Clearly it has a problem on its hands.

“We acknowledge the inconvenience this may cause in the market but this is to ensure that Samsung continues to deliver the highest quality products to our customers. We are working closely with our partners to ensure the replacement experience is as convenient and efficient as possible.”